NOC | Postmaster

Network Operation Center & Postmaster Specialist

This page is intended for Network Administrators and E-mail Server Administrators facing issues with Specialist and their customers. If you are a customer of Specialist, please navigate to the “Suporte Técnico” menu for assistance.

What triggers an IP to be blacklisted?
If our system detects any instances of spam from an IP address, we will notify the responsible party identified through WHOIS. In the event of repeated occurrences or if there is no response from the notified party, the IP/Range will be added to our blacklist.

What leads to a domain being blacklisted?
As a rule, we aim to avoid blacklisting domains or specific senders. However, there are instances where it becomes necessary. For instance, some spammers utilize dynamic IP connections or “zombie machines” for spamming, changing servers each time. In such scenarios, the domain used by the spammer will be blacklisted.

My IP or domain has been blacklisted, how can I have it removed?
The only means of contacting us is by emailing security@specialist.srv.br. In your email, please provide a detailed explanation of the situation concerning your IP or domain and the measures taken to resolve the issue. Kindly refrain from sending emails with urgent requests for removal and instead, follow the outlined procedures in a polite manner.

Tips for avoiding blacklisting:

Ensure that your mail server’s IP has a properly configured reverse DNS, and that the reverse DNS names match the server’s IP. You can use the Terra tool at https://mail.terra.com.br/postmaster/ to validate the reverse DNS.
Check if your IP is listed on any blacklists using the MX Toolbox tool at https://mxtoolbox.com/blacklists.aspx.
Properly set up an SPF entry in your DNS.
Familiarize yourself with technologies such as DomainKeys, Sender ID, SPF, SRS, DMARC, and others that help ensure the legitimacy of your emails.
Read additional tips and resources at https://postmaster.aol.com, https://postmaster.msn.com, and especially https://postmaster.live.com/snds and https://postmaster.google.com for monitoring purposes.

Information about our Network:

Up to this point, we are currently established across three distinct networks to ensure redundancy.

Our primary data center is EVEO’s, located in Cotia/SP, under ASN 53107.

We also have servers in AmazonAWS, under ASN 16509, with its data center in various cities near São Paulo/SP, and also in G2G Jundiaí’s data center (formerly Maxiweb), located in Jundiaí/SP, using IPs under ASN 28140. This one has a Looking Glass (LG) at lg.maxiweb.com.br for public queries.

As there are multiple IPs from different networks, we do not provide our IP prefixes for security reasons, but you can check them by the ASN and see how the routes are to reach them. All networks/DCs in use have multiple IP Transit links and are part of Brazil’s largest internet exchange, IX-SP.

We do not block ping requests based on ICMP packets; however, we block based on UDP packets.

For further questions or to contact us regarding any matter, please send an email to security@specialist.srv.br or call INOC-DBA at phone number 28140*100.